You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
70 lines
2.8 KiB
70 lines
2.8 KiB
/** @file
|
|
IA-32/x64 AsmEnablePaging32()
|
|
|
|
Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
|
|
This program and the accompanying materials
|
|
are licensed and made available under the terms and conditions of the BSD License
|
|
which accompanies this distribution. The full text of the license may be found at
|
|
http://opensource.org/licenses/bsd-license.php.
|
|
|
|
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
|
|
|
|
**/
|
|
|
|
|
|
|
|
|
|
#include "BaseLibInternals.h"
|
|
|
|
/**
|
|
Enables the 32-bit paging mode on the CPU.
|
|
|
|
Enables the 32-bit paging mode on the CPU. CR0, CR3, CR4, and the page tables
|
|
must be properly initialized prior to calling this service. This function
|
|
assumes the current execution mode is 32-bit protected mode. This function is
|
|
only available on IA-32. After the 32-bit paging mode is enabled, control is
|
|
transferred to the function specified by EntryPoint using the new stack
|
|
specified by NewStack and passing in the parameters specified by Context1 and
|
|
Context2. Context1 and Context2 are optional and may be NULL. The function
|
|
EntryPoint must never return.
|
|
|
|
If the current execution mode is not 32-bit protected mode, then ASSERT().
|
|
If EntryPoint is NULL, then ASSERT().
|
|
If NewStack is NULL, then ASSERT().
|
|
|
|
There are a number of constraints that must be followed before calling this
|
|
function:
|
|
1) Interrupts must be disabled.
|
|
2) The caller must be in 32-bit protected mode with flat descriptors. This
|
|
means all descriptors must have a base of 0 and a limit of 4GB.
|
|
3) CR0 and CR4 must be compatible with 32-bit protected mode with flat
|
|
descriptors.
|
|
4) CR3 must point to valid page tables that will be used once the transition
|
|
is complete, and those page tables must guarantee that the pages for this
|
|
function and the stack are identity mapped.
|
|
|
|
@param EntryPoint A pointer to function to call with the new stack after
|
|
paging is enabled.
|
|
@param Context1 A pointer to the context to pass into the EntryPoint
|
|
function as the first parameter after paging is enabled.
|
|
@param Context2 A pointer to the context to pass into the EntryPoint
|
|
function as the second parameter after paging is enabled.
|
|
@param NewStack A pointer to the new stack to use for the EntryPoint
|
|
function after paging is enabled.
|
|
|
|
**/
|
|
VOID
|
|
EFIAPI
|
|
AsmEnablePaging32 (
|
|
IN SWITCH_STACK_ENTRY_POINT EntryPoint,
|
|
IN VOID *Context1, OPTIONAL
|
|
IN VOID *Context2, OPTIONAL
|
|
IN VOID *NewStack
|
|
)
|
|
{
|
|
ASSERT (EntryPoint != NULL);
|
|
ASSERT (NewStack != NULL);
|
|
InternalX86EnablePaging32 (EntryPoint, Context1, Context2, NewStack);
|
|
}
|